With each tractor brand labeling their tractor models with different numbering systems, it’s hard to know which tractors are comparable and what each tractor is capable of.  John Deere came out with a new naming and numbering system in 2008. If you are looking at John Deere tractors that are older than 2008, the system we are about to explain won’t be applicable.

Understanding the Numbers (and letters)

Each compact utility tractor and utility tractor tractor model number consists of four numbers followed by one or two letters. 


  • The first number in the model designates which series the tractor is in. The smaller the series number, the smaller the tractor is. John Deere currently has nine tractor series that are numbered 1-9.
  • The remaining three numbers represent the approximate engine horsepower.
  • The first letter at the end of the numbers specifies the trim level and capability of the tractor. The closer to the beginning of the alphabet the letter is, the fewer features it has.
  • If there is a second letter (most models only have one), it indicates the tractor configuration, ie: if it has tracks or if it is a narrow-profile or high-crop tractor.

Model Number Breakdown

Let’s take a look at how this system works with actual model numbers.

Tractors: 6120E, 6120M, 6120R, 6155RH

Take into consideration the model numbers listed above. All of the models are 6 Series tractors with engine horsepower of approximately 120, except for the 6155RH which has approximately 155 hp.


In the instance of the models listed above, the 6120E tractor would have the least amount of features. The ‘E’ model tractors are equipped with the basic must-have features. These models generally fall at a lower price point than comparable models of a higher trim package. The 6120M has more features than the 6120E but is not fully feature-loaded. The 6120R and the 6155RH are both fully feature-loaded. The ‘R’ models generally have a higher price point than ‘E’ and ‘M’ models but they also provide you with more options and features.


The 6155RH tractor has a different configuration than the other models, as denoted by the ‘H’ at the end of the model number. The ‘H’ signifies this is a hi-crop tractor. High-crop tractors have higher ground clearance than normal models so the tractor doesn’t damage the top of crops.


Shop John Deere Tractors | Contact Us to Learn More